The Capitol Albums, Volume 2 is a box setcompilation composed of The Beatles' 1965 American Capitol Records releases. The set, which contains stereo and mono versions of all 92 tracks (with all of the tracks on The Early Beatles and many of the tracks on Beatles VI being released in stereo on compact disc for the first time) was announced on 22 March 2006.

Differences between the stereo and mono mixes are one of the main draws for collectors. There are also a few significant musical differences to other versions of these recordings, such as a false start on the stereo version of "I'm Looking Through You".

As with The Capitol Albums, Volume 1, the CDs did not contain the original George Martin mixes released in Britain in the 1960s. Instead, the CDs were mastered from tapes prepared by Capitol A&R executive Dave Dexter, Jr., who, in 1965 took sub-master tapes from Capitol Records' vaults and added reverb to several tracks and simulated stereo on mono tracks.

The official release date of 11 April 2006, was the 42nd anniversary of The Beatles holding a record 14 positions in the Billboard Hot 100 chart. This was one week after The Beatles monopolized the top 5 positions in the Billboard Hot 100 chart. The UK release was slightly earlier than the official date. Some advance copies were circulated and pre-orders were also shipped early.

The box set debuted on the Billboard 200 album chart on 29 April 2006, at number 46, with approximate sales of 27,000 copies. It was awarded a gold record by the RIAA on 19 May 2006.

Box sets and sampler discs made available prior to the 11 April release date have incorrect mono versions on Beatles VI and Rubber Soul. The incorrect mono versions were only released in this set. These "fold-down" mono versions are actually the stereo mix consolidated into both speakers. Although the versions are technically in mono (in the sense that the sound in both the right and left channels is the same), they are not the actual mono mixes released by Capitol in 1965.

Beatles author Bruce Spizer, who also wrote the set's in-depth liner notes, told The Beatles fan website whatgoeson.com that a "third party mastering facility incorrectly sent stereo-to-mono mixdowns" to be pressed rather than the vintage mono mixes.[3]

The mistake was understandable, as the US mono mixes of the vinyl release of The Early Beatles and Help! were fold-down versions of the stereo mixes. But, the US vinyl release of both Beatles VI and Rubber Soul actually had different mono mixes. It was initially unknown whether this error was restricted to one pressing plant, or all pressings, but now seems to involve all sets prior to the issue of the "corrected" version.

An explanation for the mistake given at the time was that Capitol anticipated that the stereo versions would sometimes be played back in mono, and wanted to test how they would sound if played that way, (for Beatles VI and Rubber Soul; this concern not being an issue for the other two) and so made fold-down copies of the stereo versions of these just to test how they would sound in mono, and by mistake someone caused these recordings to be issued in lieu of the true mono mixes.

The easiest way to tell if a particular copy has the correct mono mixes is to check the total playing time of the discs on a CD player. Discs with the correct mono mixes have a slightly longer playing time.